The best fertilizer for your lawn and garden is homemade compost, made from food scraps, lawn clippings, and fall leaves. If you still need store-bought products, here are a few tips:

Compost and Soil Improvements: Commercially made compost has high levels of naturally occurring phosphorous and nitrogen that is released gradually and is absorbed more easily by plants. Other soil improvers, such as worm castings, Epsom salts and decomposed organic matter called humates, add nitrogen, phosphorus, and potassium. Watch out for commercial fertilizers, even those labeled "organic," that contain harmful ingredients, such as animal byproducts or sewage sludge. Animal byproducts, such as bone meal or fish meal, may have come from industrial farming operations, and sewage sludge, could be contaminated with diseases or heavy metals.